Some messaging scenarios require Light message queue to support a large number of topics, such as MQTT, AMQP protocol, its multi-level topic sending and subscription can be set at will, and the number of multi-level topics is very large, the original RocketMQ topic It is resource-heavy, and it is difficult to support millions or more of lightweight multi-level topics.

Let's define Light message queue as （LMQ）

Light message queue (LMQ) needs to implement multi-dimensional dispatch of a message based on ConsumeQueue, and a message can support multiple lightweight queue consumption。

Light message queue (LMQ) needs to implement multi-level topic management, so topic metadata also needs adaptation management, such as topic verification, data cleaning and so on.

Light message queue (LMQ) needs to implement lightweight queue consumption offset management